What would you do if another country, many times more populous and powerful, decides that it wants Canada's water and, after listening to all the reasons why it cannot not simply take it, announces that it is going to do exactly that?

Would you refuse to accept the country's justification that its hundreds of millions of people desperately need the water to sustain their economy and that this outweighs any harm that would be done to the relatively small Canadian population that stands in the way? Would you expect your governments to resist? If your answers are yes, then you have an idea of the position of the Tsilhqot'in people.

The federal cabinet is expected to debate Tuesday a proposal for a copper-gold mine near Williams Lake, B.C. The mine would destroy the traditional lands and the sacred Teztan Biny (Fish Lake) of the Xeni Gwet'in and its sister Tsilhqot'in nations. The company behind the proposal, Taseko Mines Ltd., says the mine would generate $5-billion in economic activity over 20 years - a welcome prospect to the province and local towns hit hard by job losses. Taseko also says it plans to create an artificial lake that would eventually be home to the offspring of the 90,000 trout that would be killed when the company uses Fish Lake to store mine tailings.

Should the cabinet approve the proposed Prosperity Mine, our theoretical water-hungry foreign power could argue that taking what it wants from Canada would be no different than what Canada is doing to its own first nations. A "yes" vote would be a declaration that might is right and greed is paramount.

Our message has been clear: No amount of money could compensate for what this mine would do to our people and the land we treasure. We have played by the federal government's rules to make our case, and now we expect it to do the same.

After 60 days of hearings during which witnesses overwhelmingly opposed the mine, a Canadian Environmental Assessment Agency Review Panel reported that the project would cause significant and irreparable harm to our rights, our future generations and the environment on which we depend. It also found that no proposed mitigation would address the harm that would be caused.

The report is too long to detail. Suffice it to say that federal government departments raised serious concerns, and aboriginal and environmental groups were 100 per cent opposed to the mine. We have since learned that the B.C. government previously turned down a small lodge expansion in the same area because it would have hurt the environment and aboriginal rights.

Taseko says no great harm would result from gouging out a 35-square-kilometre open-pit mine that would kill a lake, streams, wildlife, forests and our rights and way of life. Inexplicably, the B.C. government agreed with this patently ridiculous position. The federal government cannot make the same mistake. In fact, no cabinet has ever overridden a report by an environmental assessment review panel.

We are not against all mining, but we cannot allow this poster child for all that is wrong with the system to proceed. It would be a catalyst for confrontation, not co-operation.

The Assembly of First Nations notes that federal acceptance of the mine would expose the environmental-assessment process as useless and the government's claims of respect for aboriginal culture as hollow. The AFN, the Union of B.C. Indian Chiefs, B.C.'s the First Nations Summit and others have pledged to help us defend against what we believe would be an unjust federal decision.

If the government can sell out the Tsilhqot'in in this case, it can sell out others too - and not just natives. Which is why, if denied justice, we will be forced to act. It is why first nations across the country see this as an issue of national importance. It is also why Canadians have a vested interest in seeing our rights and way of life protected.

Marilyn Baptiste is Chief of the Xeni Gwet'in of the Tsilhqot'in Nation and a founding member of British Columbia's First Nations Women Advocating Responsible Mining.